From owner-svn-src-all@freebsd.org Tue May 3 18:19:51 2016 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 17919B2A615; Tue, 3 May 2016 18:19:51 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from bigwig.baldwin.cx (bigwig.baldwin.cx [IPv6:2001:470:1f11:75::1]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id E6B291E51; Tue, 3 May 2016 18:19:50 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from ralph.baldwin.cx (c-73-231-226-104.hsd1.ca.comcast.net [73.231.226.104]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id 75163B93A; Tue, 3 May 2016 14:19:49 -0400 (EDT) From: John Baldwin To: Bruce Evans Cc: Pedro Giffuni , "Ngie Cooper (yaneurabeya)" , src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r298933 - in head: share/man/man9 sys/amd64/include sys/dev/acpica sys/dev/drm2 sys/dev/drm2/i915 sys/kern sys/sys sys/x86/acpica sys/x86/x86 Date: Tue, 03 May 2016 11:19:44 -0700 Message-ID: <1928389.rOu33C1eaq@ralph.baldwin.cx> User-Agent: KMail/4.14.3 (FreeBSD/10.2-STABLE; KDE/4.14.3; amd64; ; ) In-Reply-To: <20160504031930.A3395@besplex.bde.org> References: <201605021800.u42I0cjK084243@repo.freebsd.org> <8989101.JIAk4LJusf@ralph.baldwin.cx> <20160504031930.A3395@besplex.bde.org> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.7 (bigwig.baldwin.cx); Tue, 03 May 2016 14:19:49 -0400 (EDT) X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 03 May 2016 18:19:51 -0000 On Wednesday, May 04, 2016 03:58:40 AM Bruce Evans wrote: > On Tue, 3 May 2016, John Baldwin wrote: > > > On Tuesday, May 03, 2016 03:52:56 PM Bruce Evans wrote: > >> On Mon, 2 May 2016, Pedro Giffuni wrote: > >... > >>> TBH, I thought so too, but I avoided applying such changes to headers, > >>> and I haven't touched _bitset.h, > >> > >> _foo.h headers cannot use howmany() due to namespace pollution. > >> > >> _bitset.h was already broken, unless it is supposed to be kernel-only -- > >> it uses howmany(). It is kernel-only according to its documention -- > >> bitset is only documented in kernel manpages (in a single unreadable one > >> than is linked ad nauseum). > > > > cpuset.h is used in userland for cpuset_getaffinity(2), etc. > > > >> It is otherwise fairly clean. It defines the symbols BITSET_DEFINE, > >> BITSET_T_INITIALIZER, and BITSET_SET in the application namespace > >> This is not completely clean for a _foo.h header. All other BITSET* > >> macros are already in bitset.h I think only BITSET_DEFINE should be > >> in _bitset.h (for use declarations in other headers). > >> > >> select.h avoids this problem by defining its own howmany() macro. This > >> seems to be correct except for the bogus ifdef around the private macro. > >> This ifdef is a little more than a style bug (verboseness) -- it breaks > >> detection of other definitions that might be different. Lexical > >> differences wouldn't matter, but it is easier to never have them. > >> > >> Old versions of select polluted . The select macros just > >> used howmany(). howmany() was in too. > > > > I would be happy to fix _bitset.h and _cpuset.h to not need sys/param.h. > > However, they also use NBBY which is defined in sys/param.h. _sigset.h > > gets around this because it uses an array of uint32_t and hardcodes a > > shift count of 5 in _SIG_WORD() and a mask of 31 in _SIG_BIT(). If you > > think it is fine to hardcode '8' instead of 'NBBY' I'll do that. Hmm, > > sys/select.h hardcodes '8' for _NFDBITS, so I guess that is fine. > > NBBY can be cleaned up too. I rather like it, but it is bogus in C90 > since it is spelled CHAR_BIT there, and it is now more bogus in POSIX > since POSIX started specifying 8-bit bytes in 2001. Thus 8 is the > correct spelling of it in the implementation where you don't want to > expose a macro that makes it clearer what this magic 8 is. Ok. > BTW, I don't like select's and bitset's use of longs. Using unsigned > for select is a historical mistake. Bitset apparently copied select > except it unimproved to signed long. Bitstring uses unsigned char with > no optimizations. Sigset uses uint32_t with no obvious optimizations, > but compilers do a good job with with it due to its fixed size. I doubt > that the manual optimization of using a wider size is important. I agree, but cpuset_t is already part of the ABI in existing releases. :( Changing it to uint32_t would break the ABI for big-endian platforms. -- John Baldwin